Polymers



Patented Nov. 27, IMS

UNITED STATES PATENT OFFICE POLYMERS Norman Gail Fisher and Richard Haven Wiley, Wilmington, Del., assignors to E. I. du Pont de Nemours & Company, Wilmington, DeL, a corporation of Delaware No Drawing. Application September 3, 1942, Serial No. 457,144

1 Claim.

tion of'new intermediates for textiles, bristles, 5

transparent sheeting, coated fabric, electrical insulation, and the like. Other objects will appear hereinafter.

These objects are accomplished by, the following invention of synthetic linear condensation polymers containing recurring spiro linkages; i. e., linkages formed by two rings joined together by a carbon atom common to both rings, said spiro linkages being an integral part oi. the linear polymeric chain. The products of this invention may be prepared by reacting under polymerizing conditions bifunctionally spiran-forming reactants, i. e., either (1) a mixture of at least two biiunctionally spiran-forming reactants, or (2) a mixture of linear polymer-forming reactants containing spiro linkages which will be incorporated as an integral part of the polymer chain or (3) a monomeric bifunctionally spiran-forming compound.

Spiro compounds are cyclic compounds containing two rings in which the two rings are joined by one atom (that starred below) common to both, for example:

CHsCHs CHICK; on, m cm This compound is diiierent from:

CHICK! CHICKS In a second type, units of two or more rinrs united boxylic acid: 3o

45 acid:

-by spiro linkages are separated by connecting radicals free from spirolinkages:

I" L .l.

densation of two biiunctlonally linear spiranforming compounds is the reaction of tetrakis (mercaptomethyl) methane and cyclohexo anemone-1,4:

nscn omen -ciancm c +=C 0 o 0: H503! SOHsBH CHaCHa son cms on on K /1 BCHi onls cnlcnf Here the reaction involved is that of thioketal 20 formation; i. e., condensation of ketone and mercaptan. I

Spiro polymers can likewise be prepared from the linear condensation of bifunctional molecules one or more oi which contain a spiro linkage in 26 such a way as to incorporate the spiro linkage as a part oi the polymer chain, tor example, using hexamethylene glycol and spiroundecane dicar- This rea'tion involves-polyester formation as described in U. 5. Patent 2,071,250 as the means of 4 securing the polymeric splran.

Still another method for the preparation of linear spiropolymers involves the self-condensation of a bifunctionally spiran-forming monomer such as 1,4-diaminocyclohexane-L4-dicarboxylic HsN CHiCHl NH: CO-NH CHICK! 60 This reaction involves polyamide formation.

In the above discussion the term biiunctionaL. ly spiran-iorming" is used in the sense that there are two sets of reactive groups each of which is capable of forming spiro groups. T us, from this 65 standpoint tetrakis (mercaptomet l) methane angles are fixed in space. i culiar structure the degrees present in ordinary linear polymers,

that the products have new properties such as high softening point and low solut a bifunctional m that a has two sets of reactive groups which can form spiro linkages:

nsom omen o I nsom omen The groups included in I can form a spiran with cyclic ketone; i. e., cyclohexanone, as can also those in 11. With another bi-functional spiranforming reactant such as cyclohexanedlone each pair of --SH groups, I and 11, can react with a carbonyl, (F-'0, group of the cyclohexanedione and on repetition a linear condensation polymer is formed. It is to be noted that although the compound tetrakis (mercaptomethyl) methane has four mercaptan groups it is still only bifunctional for the purposes of spiran formation.

Similarly, the compound noio omcnf oom although containing two amino and two carbomlic acid groups, making four groups, yet is bifunctional for the purposes of spiran formation because the groups must react in pairs to form spiran linkages.

The polymers obtained from, these reactions are particularly desirable because they contain spiro atoms, 1. e. atomsin omcn /NK| Because of this peare restricted.

The result is bility, both of which are of that importance in the application of synthetic linear polymers to industry.

The more detailed practice of the invention is illustrated by the following examples, wherein parts given are by weight. There are or course many forms of the invention other than these specific embodiments. 1

ExAlIlI-II Preparation of a spiro polymer from tetrakis (mercaptomethyl) methane and .CIICZOMZGM! dime-1,4

In parts of purified dioxan were dissolved 2.0 parts of tetrakis (mercaptomethyl) methane having a M. P. or 7243* C. and 1.12 parts by weight of cyclohexanedione-1,4, M. P. 'l8-'7'7.5 0..

The solution was cooled well and hydrogen chloride gas was passed in for a short time. No precipltate appeared until the solution came to room temperature when a cloudiness appeared followed I by continuous precipitation until the whole mass was a white solid. The solid was removed from the test tube and heated under vacuum on a ste'ambath to remove the solvent This left a white powder, the polymeric spirothioiretal oi 1,4-cyclohexanedione. and tetrakis (mercaptomethyl) methane. This is insoluble in metacresol, formamide and butyl cellosolve, and has a melting point or 314-313 C.

The procedure was repeated using 3.948 parts by weight or 0.353 mol of the diketone and 7.051 parts by weight or 0.353 mol of the mercaptan.

. The reaction product was entirely similar in appearance to that above described.

The product was found to be insoluble in the following solvents: formamlde, phenol, metaof rotational freedom,

aasaeea cresol, butoxyethanol, piperasine, furiural, tetralin, cyclohexanediol, dimethylaniline, oamphor, thiophene, chlorobenzene, carbon tetrachloride, and carbon disulflde. It was slightly soluble in boiling naphthalene and soluble in boiling anthracene. A molecular weight determination in anthracene gave a value of 613.

The tetrakis (mercaptomethyl) methane used above was obtained through the hydrogenation of the sulfur compound obtained from the treatment or tetrakis (bromomethyl) methane and- The cyclohexanedione-1,4

sodium tetrasulflde. was obtainedby the method of Meerwein, Ann. 398, 248 (1913).

murulI Preparation of a who polymer from tetrakis (mermptomethvl) methane and 'dodecanedione-2,11

A solution of 1.0 part by weight (0.005 mol) of tetra-iris (mercaptomethyl) methane and 1.13 parts by weight of dodecanedione-2,1l (0.005 mol) in 10 cc. of purified dioxan was prepared and cooled. Hydrogen chloride gas was passed into the solution for a short time and the solution was allowed to warm up until precipitation had set in. After proceeding thus at room temperature for five minutes, the solution was warmed slightly as the which the valence j I agents such as alumina HCl was passed in. On standing, a precipitate of the polymeric spirothioketal of dodecanedione- 2.11 and tetrakis (mercaptomethyl) methane was formed and separated by filtering and drying. It had a melting point of 153-167" C.

' The polymer was partially soluble in to give a solid having a melting point oi. 154-15e C. The residue was insoluble in benzene but soluble in phenol and had a M. P. of 158-168 (3.

. wherein a: is-an integer; spiropolyesters such as that which can be prepared from the polyester-iflcation, accomplished through the simultaneous application of heat (over C.) and removal of the water formed in the self-condensation (a process dlsclosed'in U. S. Patent 2,071,250) 01 1,4-dihydroxy-1,4-cyclohexane dicarboxylic acid obtained in turn from 1,4-cyclohexanedione through its reaction with hydrogen cyanide (see Berichte 40, 2890 (1907)) which has the (OllOW'. ing structure:

wherein :c is a plural'integer; spiropolyamides similar to that which can be prepared by the self-condensation o1 lA-diamino-Lwyclohex anedicarboxyiic aoid'described by Zelinsky and Schlesinger, Ber. 40, 2888 using the procbenzene roupe on different carbon atoms.

ess or polyamide formation as disclosed in "com: a/-

U. 8. Patent 2,071,250 which has the structure:

essa- -nianner dsscs'ibedinthe examples above :s-being plural integer; spiropolyamides such i those prepared by the methods of condensation described in U. 8. Patent 2,071,250, from a diamine and a dibasic spiro acid such as 2,8-spiroheptanedicarboxylic acidp epared by Backer et al., Rec.

'rrav. chim., 50, 221 (1981) which polysmides have the formula V OKs 03s v wherein :c is a plural integer; spiropolysmides such as those prepared in'sccordance with the procedure given in U. 8. Patent 2,071,250, from 3 disbut be conducted along those lines toleadtothioketaiorthioacetaliormh' common solvent andtreated withan acid cataortheymay betreatedinameltwitha ethoxyethanol, cyclohexane, anthracene, thiophene, iurane, tetrahydroturane, phecyclohexanol. The reaction mixture may be subjected to controllediprolonged heating, in

2,6-diamino spirohcptane which diamine has been describedby Jansen and Pope, Chemistry and Industry, 51, sis (was) spiropolyamides such as those prepared from 2,8-diamino spiroheptane and 2,8-spiroheptanedicarb0xylic acid by the 7 method described in U. 5. Patent 2,011,250; interpolymers such as those preparedi'rom 1,4-41- hydroxy-lA-cyciohexane dicarboxylic acid or other pobe'ster forming compositions, a' diamine v such as 2,6-diaminospiroheptane, and a dibasic acid such as 2,6-spiroheptanedicarboxylic acid or other spiran-i'orming groups and combinations by the methods oi polycondensation described in the above-mentioned patent,.U. B. 2,071,250, an'd -;others.-'-

a particularly valuable subgenuso! the inven-.

tion is that of the polymeric spirothioacetais including spirothioketals. In the preparation of spirothioketals and spirothioacetals, it is not Q necessary that the diketones dodecanedione 2,11 or cyclohexanedione-M be used. Any compound containing two carbonyl groups whichwill lead to the formation or allncal polymer having spiro linksges may be'used. As examples 0! such dicarbonyl compounds which will react to methyl) methane are: aliphatic diketones such as acetyi acetone, acetonyi acetone, and octsdione- 2,'l; aromatic diketones such as diacetobenzene; mixed aromatic aliphatic diketones such as bensoyl acetone: alicyclie diketones'such as 1.3-

cyclopentanedione. Inaddition such dialdehydes as suceinic dialdehyde, adipic dialdehyde, or

terephthalaldehyde may be employed. Inthis phase of the invention a preferred modification is that wherein any organic compound having a quaternary carbon Joined to four alkyl groups each oi which has a mercaptan group on the carbon next to the quaternary carbon is reacted with any diketaldonyl compound, 1. e. a comhyde or ketone type. that wherein any diketaldonyl compound having one but preferably both of the ketaidonyl groups in a ring is reacted with an aliphatic tetrathiol, i. e. an aliphatic compound having I tour thiol Thereactionneednotbecarriedoutintbe ct them prior to starting the reaction byapplying heatormaybesddedtothemixture oireactants to start the reaction.

'I'he'invention is thus generic to linear containing spiro linkages which are present as the result 0! a polycondensatim reaction thatiorms recurrent spiro ea or involves 1%, actants containing preiormed spiro linkages. becomes. part of the polymeric chain. The chemical type of linkage whether ester, amide, thioamide, imidoether, thioimidcether, arnidine, urethane, thiourethane, thionurethanm I dithiourethane, urea, thiourea, guanidine,

ketal, thioether, thioacetal, thioketal, sultone; suiionium salt, azomethine, amine, quaternary ammonium salt, or anhydride is not the essential partot the invention. Anya: the reaction types known tothe chemistskilied in the art may be. applied to the iormation of recurrent spiran linkages and any type or. chemical grouping knowntothoseskilledintheartmayb'eusedto form the polymer in the practice or the invention.

, The'distinguishing feature that la -important is the characteristic spiro grouping oi the atoms in which one atom is shared in common by two rings.

This groupins, may be preeentin the polymer give spiro linkages with e. g. tetrakis(mercaptothrough-being lowed by the polymerisation m.

action or through being present in the. molecule to be 1 i Particularly preferred are the linear condensationspiropolymers wherein the spiro carbcm iormpartotabtoiimemberedring. oithese the spirothioketals having spiro carbonsattachedj; totwosuliuratomsina5to 'I'heproducts of this invention may be fibers for textiles.- monoills for bristles, transpound having two carbonyl groups of the alde- A Another modification is The two reactants may be dissolved in-a' I 8 memberedring are especially preierred 

